Wireframe
You might say
Hold off on colors—sketch a gray page skeleton first: header, hero, three cards, footer, just the positions.
A wireframe is the page skeleton drawn in gray blocks and placeholder lines—it fixes "what goes where" before any colors or fonts.Sketch the page in gray blocks first: how tall the header is, what sits in the hero, where the button goes. With positions settled, colors and fonts can be adjusted without reworking the layout. The wireframe fixes positions; the visual design handles colors and fonts.
Know first
Further reading